Such a rotor is known from the publication U.S. Pat. No. 7,708,529 B2. The rotor has a C-shaped, radially outwardly open circumferential groove in a rotor disk, the C-shaped circumferential groove having recesses at the side portions thereof. The blade roots are swiveled in through these recesses. This rotor also has an annular securing device that is fastened between a bottom side of the inner shroud of the blades and a radially outer surface of the rotor disk to prevent the blades from swiveling out of the circumferential groove.
This design is particularly disadvantageous since the transitions from such recesses to the projections of the rotor configured at the circumferential groove can weaken the rotor disk in terms of structural mechanics. This can occur to the point where such rotors can experience a notching effect at these transitions, allowing cracks to form accordingly at these locations. In the worst case, it can even lead to failure of a rotor.